Patent GB-901546-A (GB)
Title: Water-soluble azo dyestuffs containing esterified dihydroxypropyloxy groups
Inventor: LANGE GUENTER
Filed: 1959-12-08
Abstract: The invention comprises azo dyes derived from a benzenic diazo component and a naphtholic or enolic coupling component which contain at least one b ,g -dihydroxypropyl radical, combined by way of oxygen, which is esterified in the g -position with sulphuric acid or an organic sulphonic acid and which contains altogether at least one of the groups sulphonic, carboxy and sulphuric acid ester.  The dyes may be made by treating appropriate dyes, or intermediates, containing a b ,g -dihydroxypropyl group with sulphuric acid or a halide, anhydride, acid sulphate or pyrosulphate thereof, or those containing a sulphonic and/or a carboxylic group and a b ,g -dihydroxypropyl group with an organic sulphonic acid or a halide or anhydride thereof, or by treating appropriate dyes or intermediates containing a b ,g -epoxypropyl group with sulphuric or a sulphonic acid, and, if necessary, the dye is formed by known methods from the intermediates.  Preferred dyes are those of formula (D-N=N-E)-(OCH2CHOH.CH2OY)p1 which may have up to 3 sulphonic and/or carboxy groups, where D is a benzene residue, E the coupling component residue, Y a residue of sulphuric or a sulphonic acid and p1 or 2, and where D and E may contain neutral substituents such as methyl, phenyl, ethoxy, chlorine, amino, mono- and di-ethylamino, benzoylamino, cyano, nitro, trifluoromethyl, sulphonamide, carboxylic acid amide and alkylsulphone groups.  D or E may also contain additional azo groups.  Especially preferred are dyes of formula <FORM:0901546/IV (b)/1> where A is the dye residue, R an organic radical, X a sulphonic or carboxy group, Z+ a cationic radical, e.g. H, NH4 or K, m O, 1 and 2, n 1 or 2 and q 1 or 2.  Dyes with especially valuable tinctorial properties are obtained from diazo components which contain the oxypropyl group but no sulphonic or carboxy groups.  Specified sulphonic acids include ethane, vinyl, b -chloroethyl, p-toluene, o-chlorobenzene, naphthalene-2- and diphenyl-p1p1-di-sulphonic acids.  When disulphonic acids are used two diazo components may be combined to give a tetrazo component. Acylation of the b  hydroxy group takes place to a slight extent. The dyes colour natural and synthetic substances containing carbonamide groups, e.g. leather, wool, silk, polycaprolactam and condensation products of adipic acid and hexamethylene diamine.  They are particularly of use on native and regenerated cellulose, e.g. cotton, linen, viscose rayon, hemp and jute.  The dyeing of cellulosic materials is preferably effected in conjunction with an alkaline treatment and a thickening agent.  Numerous examples are provided for the preparation of the dyes and their use in colouring cotton in red and yellow shades representative of the coupling components used for monoazo dyes being, 2-naphthol, 1-naphthol-4-sulphonic acid, 2-amino-8-naphthol-6-sulphonic acid, 1-acetylamino-8-naphthol-4,6-disulphonic acid, 2-naphthol-3-carboxylic acid p-sulphoanilide, acetoacetate acid anilide and 1-(3-sulphophenyl)-3-methyl-5-pyrazolone and the disazo dye 4-aniline sulphonic acid --> 3-aminophenyl-(b ,g -dihydroxypropyl) ether (sulphuric acid ester) --> 1-(4-sulphophenyl)-3-methyl-5-pipazolone, is also prepared.